Booz Allen Hamilton, Edward Snowden's employer, is one of America's biggest security contractors and a significant part of the constantly revolving door between the US intelligence establishment and the private sector.

The current of director of national intelligence (DNI), James Clapper, who issued a stinging attack on the intelligence leaks this weekend, is a former Booz Allen executive. The firm's current vice-chairman, Mike McConnell, was DNI under the George W Bush administration. He worked for the Virginia-based company before taking the job, and returned to the firm after leaving it. The company website says McConnell is responsible for its "rapidly expanding cyber business".

James Woolsey, a former CIA director was also a Booz Allen vice-president, and Melissa Hathaway, another former company executive also once worked as the top aide on cybersecurity to McConnell when he was DNI. The company headquarters in the leafy Washington suburb of McLean in northern Virginia, close to CIA headquarters and home to former and current intelligence officers.

Snowden's decision to reveal his identity as a computer systems administrator for Booz Allen Hamilton, directly handling National Security Agency IT systems, raises significant image problems for the $6bn company and its 25,000-strong staff, which has traded on a bond of trust with sensitive clients, particularly the intelligence establishment.

"Booz Allen is a committed partner not only to our clients, but also to the institution of government, the business community, the communities in which we work, and the global community," the website declares. "We leverage our management and technology consulting capabilities to help clients in a number of ways."

The company marketing is heavily oriented towards handling its client computer systems needs. Under the heading "improving public safety with analytics", it offers expertise in helping cope with large amount of collected data. In a line that reflects some of the functions Snowden performed for the NSA, the Booz Allen Hamilton said its expertise in analytics "enables organizations to process, interpret, and use massive data stores in weeks or months".

Snowden's decision to become a whistleblower also seems likely to reinvigorate a long-running debate in Washington over the role of private contractors in highly sensitive security roles. The Washington Post estimated that about a third of Americans with top secret security clearances are private contractors.

In his Senate confirmation hearings in 2010, Clapper defended the private sector's role saying: "I worked as a contractor for six years myself, so I think I have a good understanding of the contribution that they have made and will continue to make."

Booz Allen is in turn majority owned by the Carlyle Group, a giant US-based investment fund with $176bn in assets.

• This article was amended on 10 June 2013 to correct the figure for the Carlyle Group's assets.